Partisan command engaged young people from western Bosanska Krajina to harvest wheat and other crops from the valley, transporting them to storage facilities on Mount Grmeč. The workers (mostly young women) were organised into military-style units, which were merged in mid-August into the four-battalion 1st Krajina Agricultural Shock Brigade. Bursać was appointed political commissar of the 3rd Company of the brigade's 2nd Battalion. Guarded by Partisan units, the brigade completed its work despite attacks by enemy planes. Bursać was admitted to the KPJ at the end of summer 1942; at the beginning of 1943, she was president of the village committee of the United Federation of Anti-Fascist Youth of Yugoslavia (, or USAOJ). Yugoslav Partisan Tito came to Drvar at the end of January 1943, during a major Axis offensive against the Partisans (code-named Fall Weiss in German). After consulting with Đuro Pucar, the head of the KPJ regional committee for Bosanska Krajina, Tito decided to form a Partisan brigade around a battalion of experienced fighters from Drvar. Additional manpower would consist of recovered Partisans who had been wounded or ill, older men not previously in combat units and young male and female volunteers. The four-battalion 10th Krajina Brigade, intended to play a primarily-defensive role at this stage, was established on 4 February 1943; its 800 members included about 120 women. Bursać, one of the volunteers, was assigned to the 2nd Battalion and was transferred to the 3rd Battalion's 3rd Company the following month. Until September 1943, she fought the Ustaše, Germans, Italians, and anti-communist Chetniks around Grahovo, Knin, Vrlika, Livno and Mount Dinara, was commended for her courage and skill in combat, and served as a nurse. In February and March 1943, during the Axis offensive, the brigade experienced constant enemy attacks, food shortages, cold, deep snow and outbreaks of typhus. Emaciated, Bursać was transferred to the military kitchen at brigade headquarters at the beginning of spring; after a month, she was returned to her company at her insistence. When she became ill some time later, Bursać was sent home to recover. The Germans had a fortified base, Stützpunkt Podglavica, near Podglavica in the village of Prkosi (between Vrtoče and Kulen Vakuf). The base, with about 500 members of the 373rd (Croatian) Infantry Division and an artillery battery, secured the roads from Bosanski Petrovac to Bihać and Kulen Vakuf. In September 1943, the 2nd and 3rd Battalions of the